If your bathroom is like ours, it’s a steamy mess after someone’s had a shower: the window is positively dripping with water and the mirror is impossible to use – and we thought we had a bathroom extractor that was meant to cope with these issues!
While we generally clean the grille that faces down from the bathroom ceiling, what we didn’t appreciate is just how much dust and dirt builds up in the pipework and on the fan blades in the extraction unit itself. It’s only when the unit failed did we finally get to find out.
A bathroom extractor fan is usually linked to the bathroom light and, of course, mains power. The basic principle is that the unit remains idle, ‘waking up’ when the bathroom light is turned on. When the light is then turned off, the fan remains spinning for an adjustable period of time – this is to suck out the humid air (or any bathroom odours). They have an inlet grille, usually in the bathroom ceiling, then a length of 100mm diameter flexible hose that connects to the fan itself and another length of flexible hose connecting that to the outside vent. Aside from vacuuming the inlet grille to remove dust, there’s not much that can be routinely done to maintain these vent systems.
It’s easy to find out if air is flowing through the grille: simply turn the bathroom light on and hold a sheet of toilet paper against the bathroom grille. If it falls when you let go, the suction isn’t what it should be and something needs to be done.
Our fan body is, like most people’s, in the loft-space above the bathroom. It’s only fractionally larger than the diameter of the two hoses connected to its in- and outlet ports with both hoses held in place by some nylon self-locking ties. Remembering to disconnect the power source first, we removed the hoses and had a look at the fan body. The motor was housed in the centre of the duct, supported by three narrow spokes, while the fan spins in the space between the motor and the duct walls. In ours, this space was about 2cm so the fan blades are very short and it only took a little dust build-up to render them almost useless! Furthermore, a ball of dust from within the flexible hose had detached and jammed itself between the fan blades and walls.
After cleaning what we could out of the flexible hose and fan unit, we powered the extractor back up and found that the blades wouldn’t spin reliably. Clearly, it was time for a new one.
Which extractor to buy
There’s a range of fans available and almost all of them use the same 100mm connections so before buying an identical replacement, do some homework and check the specifications: If the fan is being used to control condensation and humidity, aim for one that states an air flow per hour of 10-20 times the volume of the room. Generally speaking, the more powerful they are the noisier they tend to be – of course, we can compromise to some degree by having a less powerful one running for longer but good placement of the motor body will also help control the sound. Again, a generalisation but if the motor body is significantly larger than the hose diameter then the fan blades will be longer (and so more efficient/tolerant of dust).
After finding a new unit in the local DIY/trademen’s outlets, we set about cutting its noise levels. Firstly, it’s worth remembering that it’s the vibration we need to work on: the actual noise of air being sucked up isn’t usually that noticeable. So, making sure the unit sat on its rubber feet rather than being screwed directly to a joist was the first objective. We also supported the hoses on both sides of the fan body with some scrap foam to help ‘soak up’ any vibrations before the hose touched the ceiling – we tried with and without and found this was well worth doing.
The outlet grille/vent
While not a key part of our replacement process, it’s worth checking the outside grille: these should be the ‘flappy cover’ kind if the vent is wall-mounted so they stay closed unless air is blown through from the inside – this is to reduce cold drafts when the fan is off. They also prevent insects from climbing into the hose and setting up home so, if yours is a plain open vent on a wall, it’d be worth changing it for those two reasons alone. Sadly, for any vents that face down (ones fitted to the underside of the soffit box, for example) there’s not much you can do to prevent drafts or any insect issues.